Exploring atmospheric environmental drivers of asthma among children in Shanghai, China: Evidence-informed policies are required

It is important to identify atmospheric environmental drivers of childhood asthma because asthma is the most common chronic disease in children globally. We provided an overview of the impacts of exposure to atmospheric environmental factors (e.g., meteorological factors and air pollutants) on childhood asthma, based on a series of studies with the cutting-edge environmental epidemiological methodology in Shanghai, China. Overall, we found that the prevalence of asthma among the children aged 3–7 years had increased by approximately 7 fold, from 2.1% in 1990 to 14.6% in 2019. Most meteorological factors (i.e. daily mean temperature, temperature difference, air pressure, air pressure difference, precipitation, relative humidity, sunshine and wind speed) and air pollutants (PM₁₀, PM_2.5, NO₂, SO₂ and O₃) were significantly associated with childhood asthma (p < 0.05), but meteorological factors appeared to play more important roles than air pollutants in the occurrence of asthma exacerbations. We also found that temperature variability was significantly associated with the elevated relative risk of daily outpatient visits for childhood asthma (p < 0.05). Furthermore, we conducted a systematic review on climate change adaptation measures and childhood asthma and found that there were a number of adaptation measures proposed for childhood asthma in response to climate change, including vulnerability assessment, improving ventilation and heating, enhancing community education, developing forecast models, and early warning systems. However, the effectiveness of most adaptation measures, except for improving ventilation and heating in winter, have not been explored and quantified. Since asthma is sensitive to the variation of atmospheric environmental conditions, it is critical to develop and implement appropriate climate change mitigation and adaptation strategies as global heating becomes apparent.